DE102005029671A1 - Cooling system e.g., for projector or spotlight, has cooling device partly surrounding light source for generating convection flow - Google Patents

Abstract

A cooling system for a spotlight, has a spotlight housing in which a light source mounting is arranged for receiving a light source and a reflector, which reflects the light given off by the light source to a light exit aperture of the spotlight housing. A convection cooling device (5) partly surrounds the light source for generating a convection flow which is derived from the heat from the light source. An independent claim is included for a spot light.

Description

The The invention relates to a cooling system for one Headlamps according to the generic term of claim 1.

Out WO 2004/029 507 A1, a headlamp is known, a in a headlamp housing arranged one or two sided sockeltes bulbs, the from a lamp or from a burner, for example from a Discharge lamp in the form of a metal halide lamp, consists, and a Reflector, which is the light emitted by the light source towards a front opening of the spotlight housing reflected by a transparent cover, for example a protective screen or lens disc, is closable.

• a) die Wärmestrahlung wird von den das Leuchtmittel umgebenden Bauteilen wie Reflektor, Leuchtmittelsockel und Zuleitungen zum Leuchtmittel sowie vom Scheinwerfergehäuse teilweise absorbiert, die dadurch in ihren Materialeigenschaften negativ beeinflusst werden und selbst als sekundäre Wärmequelle wirken,
• b) über die elektrischen Kontakte und über den Keramikkörper des Leuchtmittelsockels findet eine Wärmeleitung statt und
• c) die Umgebungsluft des Leuchtmittels wird aufgeheizt, steigt nach oben und zieht in einem konvektiven Kühlungsprozess kühlere Luft von unten nach.

In addition to the radiation of visible light rays produced by a burning light source in its arc or filament also lying in the infrared spectral range, non-visible heat radiation, which is delivered by the following three processes to the environment of the bulb:

• a) the thermal radiation is partially absorbed by the components surrounding the luminous means such as the reflector, luminaire base and supply lines to the illuminant as well as by the floodlight housing, which are thereby negatively influenced in their material properties and themselves act as a secondary heat source,
• b) via the electrical contacts and on the ceramic body of the lamp socket heat conduction takes place and
• c) the ambient air of the lamp is heated, rises and draws in a convective cooling process cooler air from below.

Around to support the latter process and a bogus greater To provide light output with a compact design, this consists of the WO 2004/029 507 A1 known headlight housing from an upper, cylindrical headlight housing part and a lower, cuboid-shaped Headlamp housing part, at the ventilation shafts with arranged separate ventilation ducts are. The ventilation channels are separated by lamellae, which are inside the ventilation shaft one to the air inlet openings adjacent first fin section and one to the air outlet openings adjacent second, opposite Having the first portion of the lamella kinked lamellar portion.

From the US 5,172,975 A is a headlamp with a light source, a reflector and a light exit opening in a cylindrical headlight housing known, are also formed on the convective cooling of the environment of the heat-emitting lamp circumferential, limited by fins ventilation channels. The slats are bent outside of the cylindrical headlight housing and crimped at their ends, so that on the one hand avoided the leakage of light from the interior of the headlight housing and on the other hand, the air flow is directed perpendicularly away from the headlight housing.

From the US 1 758 290 A is a headlight housing with arranged on the housing walls ventilation ducts with separate ventilation ducts, which are separated by lamellae, so that there are uniform ventilation ducts, flows through the cooling air into the interior of the spotlight housing. The projecting into the interior of the headlight housing ends of the lamellae above and below the optical axis of the headlight are again bent in opposite directions, so that the ends of the optical axis arranged above the lamellae are directed to the bottom of the headlight housing, while arranged below the optical axis Ends of the fins directed to the top of the headlight housing and both sections are interconnected in a central horizontal part, so that an improved cooling air circulation is achieved by the headlight housing by the different orientation of the located inside the headlight housing ends of the fins.

task The present invention is a cooling system for a headlight of the aforementioned Specify type, the noise emitted by a lamp heat and with the greatest possible Effect of the headlamp housing dissipates and in the interior of the headlight housing located before components the heat radiation protects and / or effectively cools.

These The object is achieved by the Characteristics of claim 1 solved.

The inventive solution provides a cooling system for one Headlamp ready, which ensures that the heat emitted by the lamp or a burner is noiseless, dissipates with maximum effect from the headlight housing and located inside the headlight housing Components before heat radiation protects and / or effectively cools.

• – das Kühlsystem vom Scheinwerfergehäuse zumindest teilweise abgekoppelt wird und dabei eine größere Gestaltungsfreiheit für das Scheinwerfergehäuse und die Unterbringung von Bauteilen des Scheinwerfers ermöglicht,
• – die von dem Leuchtmittel abgegebene Wärmestrahlung auf gefährdete oder wärmeempfindliche Bauteile wie beispielsweise die Lampenkabel von der konvektiven Kühlungseinrichtung abgeschirmt wird,
• – im Innern des Scheinwerfergehäuses befindliche Bauteile, die nicht vor der Wärmestrahlung geschützt werden können, wie beispielsweise der Reflektor, oder zu denen eine direkte Wärmeleitung stattfindet, wie beispielsweise der Leuchtmittelsockel, durch eine optimierte Ankopplung an die konvektive Kühlungseinrichtung optimal gekühlt werden und
• – eine maximafe Konvektionsströmung unabhängig von der Stellung des Scheinwerfers erzeugt wird, die auch bei geneigt betriebenem Scheinwerfer voll wirksam ist.

The solution according to the invention is based on the consideration of the as a lamp or Burner trained bulbs via the three processes above dissipate heat with the greatest possible effectiveness from the Scheinwerter dissipate by the convective cooling device includes the light source partially and generates a convection, which dissipates the heat emitted by the lamp directly, so that

• - The cooling system is at least partially decoupled from the headlight housing and thereby allows greater freedom of design for the headlight housing and the placement of components of the headlight,
• The heat radiation emitted by the illuminant is shielded from endangered or heat-sensitive components such as the lamp cables from the convective cooling device,
• - Located inside the headlight housing components that can not be protected from thermal radiation, such as the reflector, or to which a direct heat conduction takes place, such as the bulb socket, are optimally cooled by an optimized coupling to the convective cooling device and
• - A maximafe convection flow is generated regardless of the position of the headlamp, which is fully effective even when tilted headlamp.

in the Difference to the cooling systems known from the prior art, in which by the arrangement of cooling fins and cooling ducts on headlamp housing the heat radiation emitted by the illuminant of the headlamp increased Cooling air supply removed by convection is thus, according to the invention, the heat at the location of the heat source, namely taken directly on the bulb itself and with the greatest possible Effect dissipated from the headlight, leaving the interior of the headlamp housing located components and in particular heat-sensitive components either Completely or by optimal cooling be protected against overheating.

Preferably creates the convective cooling device a substantially fast laminar flow of air, that of the light source released heat as soon as possible and with the greatest possible effectiveness from the headlights, wherein the convective cooling means partially enclosing the illuminant the fast, laminar air flow also supported and effective, when the headlamp is operated tilted. The cooling fins the convective cooling device can optionally parallel to each other in the direction of gavitation, d. H. perpendicular inside the spotlight housing aligned or in particular in asymmetric heating such be inclined against each other, that in all between the cooling fins formed columns receive a substantially laminar flow of cooling air remains.

By cooling fins different length, where in particular the inner cooling fins are longer as the outer cooling fins, is a turbulence of emerging from the cooling fins heated Air kept low. Alternatively or in addition to the different long cooling fins can the cooling fins at their heat donating end also to the outside be bent so that the occurrence of the convective air flow obstructing Whirling is significantly reduced.

Prefers the cooling fins extend over the entire height of the headlight and allow thus a far-reaching separation of the cooling system from the interior of the Headlight housing.

A advantageous development of the invention is characterized in that the cooling fins too Cooling fin packs summarized in the direction of gravity above and below the Illuminant are arranged.

By the formation of cooling fin packages with several parallel or inclined to each other arranged cooling fins On the one hand, cooling air is targeted to the heat source brought and on the other hand from the heat source discharged, heated air in the above the heat source located Kühllamellenpaket to the outside of the spotlight housing derived, wherein the heated air at the cooling fins substantially laminar flows along and only at the exit from the cooling disk pack Vortex forms, so the heat load with the greatest possible Effect and in the shortest possible time Time dissipated becomes.

Preferably is the gap thickness of the formed between the cooling fins columns at least in dependence from the wall temperature of the cooling fins and the height the cooling lamella packages determined.

When heat transport within the cooling fin packets, the circulating air flow is in contact with the heated surface of the cooling fins, so that the overlying, more or less thin layer of air is heated by molecular heat conduction, it expands and undergoes a buoyancy. This buoyancy causes an acceleration of the heated air packets against gravity up to the friction forces on the wall of the cooling fins and in the interior of the flow on the one hand and the buoyancy in the resulting natural convection flow on the other hand keep the balance. For optimum cooling effect by natural convection, therefore, the friction forces must remain as small as possible, so that the influx of fresh, that is cool air, is only slightly hindered on the walls of the cooling fins. From this thermodynamic process, a cooling heat flow as a function of the gap thickness for different shaft heights of the cooling disk packs can be determined for different wall temperatures of the cooling fins. From the thus determined curves of the heat flow over the gap thickness or shaft height of the Kühllamellenpakete an optimal distance of the cooling fins for the best possible cooling while minimizing the space for the Kühllamellenpakete be determined.

In An advantageous embodiment of the invention are the Kühllamellenpakete through bilateral side plates to form a convective cooling box limited in the between the upper and lower cooling fin package trained space the lamp socket accommodates.

By the partial inclusion of the heat releasing Light source in the convective cooling box is on the one hand an optimized laminar convection flow emitted by the bulb Heat optimal dissipated and through the side panels prevents heat radiation in the not with The optimized laminar airflow impinged on the room Interior of the spotlight housing is heated and deliver the heat absorbed only via secondary emission through the headlamp housing can.

The Formation of a partially enclosing the light convective refrigeration box elevated the effectiveness of the generated convective air flow and limits the dissipation of the heat emitted by the lamp substantially the convective cooling box, so the sizing and design of the spotlight housing is not much more of constructive features to dissipate the bulb released heat is determined. this makes possible in addition to a smaller size of the headlamp housing greater degrees of freedom in the design of the headlight housing and also offers the possibility heat risk Components of the headlight in the interior of the headlight housing to embarrassed.

Preferably is not the convective cooling box much wider than the bulb itself, so the headlight housing either in the opposite direction of the emission of the headlamp End of the spotlight housing narrower than conventional headlamp housing can be formed or the interior of the headlight housing, the significantly less due to the arrangement of the convective cooling box heats up as the interior of conventional, fully ventilated headlamps, for the Housing and arrangement of cables, electronic components or other heat-sensitive components can be used.

to Shielding of the light emitted by the lamp stray light and as a protection against splashing water is the upper cooling fin package or the convective cooling box led out of the upper part of the headlight housing and covered by a cover plate, which directed to the spotlight housing having angled ends.

at the formation of a convective cooling box has the lamp socket preferably upper and lower comb-shaped forms or cuts, in the at least part of the cooling fins engages with movement scope.

By This measure is an optimal heat transfer from the lamp socket to the cooling fins or the convective cooling box guaranteed without that between the lamp socket and the cooling fins or the cooling box thermal stress occur and damage the lamp socket or the cooling fins to lead can.

to optimal cooling the heat radiation the illuminant in particular exposed reflector and to achieve a better cooling effect even when tilting of the headlamp are in the direction of radiation of the headlamp front edges of the cooling fins adapted to the shape of the reflector and essentially comprise the reflector, the leading edges of the cooling fins either rest on the reflector or attached to the reflector.

to further optimization of the heat transfer from the reflector to the cooling fins or to the convective cooling box can the back of the reflector with cooling fins be provided, the comb-shaped in between the cooling fins convective cooling box engage trained column. This is also an optimal heat transfer then ensured if the reflector opposite the cooling box or the cooling box together with the in the cooling box partially arranged light source is moved relative to the reflector.

A further relief of the reflector from the emitted by the lamp Heat radiation is achieved according to a further feature of the invention in that the reflector has ventilation openings, in the between the cooling fins culminate in a trained column.

These Another embodiment of the invention proves to be particularly advantageous in conjunction with faceted reflectors, as these provide diffuse light scattering effect, allowing the removal of individual facets or parts single facets no effect on the light distribution and minimal impact on the output from the headlamp Has light amount.

In a variant of the cooling system for a headlight a recess may be provided in the reflector formed thereby is that a circular area encompassing one or more rows of facets or a sector-shaped area comprising one or more columns of facets of the reflector is released. Through a created recess For example, a cooling air flow in into the reflector and through the reflector.

Around reduce the light losses caused by the recess, is the annular and / or columnar Recess thereby by a radially spaced, from reflecting Facets formed section covered by one possible Lamp position on the reflector axis viewed from the recess completely covered and approximately parallel to the surface of the reflector extends. In particular, the section for covering the recess by one in its dimensions opposite to the In the reflector recessed area enlarged ring and / or sector be formed, wherein the ring or the sector of facets thereby is such that it is viewed from the reflector axis arranged in front of or behind the actual surface of the reflector is. In this way there is an interruption in the reflector for the penetration the cooling air flow created at a simultaneously optically almost unchanged reflector arrangement, so that the light losses caused by the recess minimized are.

By one in particular with regard to the surface shape and the arrangement changed Forming the facets, the radially spaced, for example annular or columnar Form section to cover the recess can thereby causes be that the light distribution of the provided with the recess Reflector is not changed compared to the reflector without recess, so that the reflector arrangement generates the desired light distribution.

In A further embodiment of the solution according to the invention is between the glass vessel and the Contact pins of the bulb arranged a heat sink and on the cooling ducts of the cooling disk packs aligned.

These Further embodiment of the solution according to the invention improves the shielding endangered Components such as the electrical contacts and electrical cables in front of the heat radiation emitted by the lamp, wherein the heated Air from the lampholder up or down into the chiller packs or in between the cooling fins derived cooling ducts even if the headlight is tilted.

to optimized heat dissipation even with tilted headlights, the heat sink V-, U- or S-shaped trained and can directly in a further embodiment of the inventive solution be connected to the bulb socket.

alternative can the heat sink connected to the lamp socket, in particular with the lamp clamp become. It is essential that the heat sink as possible positively on Lamp neck is applied to the flow of hot air to the rear, that is contrary foreclose the direction of emission of the headlamp.

The solution according to the invention is suitable especially for Headlamp, in which the cylindrical bulb in axial Direction of the headlight aligned and in a central opening of the reflector is used. In this axial optical system is located the light-emitting glass cylinder of the illuminant within the Reflectors while the lamp base of the convective cooling device, that is of the Cooling fins, the cooling fin packages or the convective cooling box is bordered and adapted to the contour of the reflector Leading edges of the cooling fins to the back of the reflector for optimal heat transfer invest. As a result, even with an axial displacement of the lamp To prevent the radiation angle the greatest possible effectiveness in the Removal of the emanating from the lamp heat load ensured.

alternative the illuminant can be aligned in the direction of gravity (vertical) his and the cooling lamellae packages or the convective cooling box at Abut reflector or be connected to the reflector or the lamp aligned transversely to the direction of gravity (horizontal) and in a recess of the reflector, while the cooling fin packets or the convective cooling box abut the reflector or connected to the reflector.

Reference to an embodiment shown in the drawing, the idea underlying the invention and other features and advantages of the invention will be explained in more detail. It demonstrate:

1 a side view of a compact headlamp with a convective cooling device;

2 a partially cutaway perspective view of the headlamp according to 1 ;

3 a section through the headlights according to the 1 and 2 along the section line III-III;

4 a partial perspective view of a convective cooling box and reflector of the headlamp according to the 1 to 3 ;

5 a partial perspective view of an axially aligned, partially enclosed in the convective cooling box lamp;

6 a longitudinal section through the Scheinwerter according to 1 ;

7 and 8th a schematic representation of a reflector with an annular recess and

9 and 10 a schematic representation of a reflector with a sector-shaped recess.

In the 1 shown side view, the partially sectioned perspective view according to 2 , the cross section through the headlight according to 3 and the longitudinal section through the headlight according to 6 show a spotlight housing 1 with a central, cylindrical lamp housing 10 of the spotlight housing 1 , a lower, polygonal functional housing 11 , an upper, trapezoidal housing of the cylindrical lamps 10 protruding part 12 as well as one of the contour of the in 6 illustrated reflector 3 adapted front part 13 ,

As in particular the side view according to 1 and the partially sectioned perspective view according to 2 it can be seen in the headlight housing 1 on the usual strong ribbing in particular of the cylindrical lamp housing 10 be omitted to increase the heat-emitting surface, since the convective cooling device according to the invention for generating a convection flow through the lamp 2 , in particular via their glass vessel 21 , heat given to the upper, trapezoidal part 12 of the spotlight housing 1 dissipates and thus the inside of the headlight housing 1 protects components against a strong heat load.

The light emitting front of the headlight housing 1 is according to 6 completed by a cover in the form of a glass or a lens disk. One with the cylindrical lamp housing 10 connected headlight bracket 15 is used for transport as well as tripod attachment or suspension of the headlamp and can be axially to the center of gravity displacement on the lamp housing 10 be adjusted.

In operation of the headlamp produces the burning lamp 2 in their arc or in their filament heat, as heat radiation from the surrounding components, in particular from the reflector 3 , the headlight housing 1 and the front cover or lens 14 is partially absorbed, resulting in a significant stress on these components, which consist of heat-resistant materials and must be sized accordingly. In addition, these components but also act as a secondary heat source, which in turn emits heat to the environment or to other components, especially in the interior of the headlamp, so that, for example, a ribbing of the headlight housing 1 must be provided in order to provide a sufficiently large heat-emitting surface.

Furthermore, there is an immediate heat transfer via the contact plug 41 . 42 and supply lines 171 . 172 as well as over the ceramic body of the lamp cap 22 ,

Finally, it leads from the burning lamp 2 given off heat to the ambient air of the lamp 2 is heated, the heated air rises in the direction of gravity upward and trailing cooler air from below. In order to support this Konvekti onsströmung appropriately sized air inlets are provided on the underside of the headlamp and form air outlet openings on the top of the headlamp in order to deliver the heated air to the environment can. It is to be ensured by the shape of the air inlet and air outlet slots that no stray light from the headlight housing 1 exit.

Out the above reasons are the trained according to the prior art headlamp housing in terms on the headlight power large, to the of the burning lamp can absorb outgoing heat loads and strong on its outer surface profiled to the heat donating area sufficiently large and a sufficiently large one convection to ensure, without light coming out of the headlamp housing.

In contrast, in the Invention proper cooling system for headlamps targeted heat transfer from the burning lamp 2 emitted heat, in which the heat radiation to vulnerable components, such as in accordance with 2 and 3 the lamp cables 171 . 172 and contact plug 41 . 42 , into the pins on the lamp socket 22 ( 5 and 6 ) the lamp 2 be plugged through a heat sink 7 is shielded, and components that can not be protected from heat radiation, such as the reflector 3 , or to which an immediate heat conduction takes place, such as the lamp socket 4 be cooled by an optimized coupling to heat dissipating components. Furthermore, the convection process is optimized by a convective cooling device so that a fast, laminar air flow is created, which is also effective when the Scheinwerter example is operated inclined.

For this purpose, the cooling system according to the invention according to the 2 to 6 a convective cooling box 5 on, consisting of several parallel and arranged in the direction of gravity, plate-shaped cooling fins 6 as well as two side plates 51 . 52 consists. The cooling fins 6 are to a top and bottom cooling fin package 61 . 62 summarized and close in between a part of the lamp 2 , in particular the lamp base 22 or the lamp base 22 receiving lamp socket 4 one. Between the individual cooling fins 6 are column 60 designed so that between each two cooling fins 6 Cooling wells are formed on the cool air from the lower cooling fin package 62 tracked and heated air from the upper cooling fin package 61 is dissipated.

The between the cooling fins 6 formed cooling ducts are dimensioned so that an optimal, fast, laminar air flow for the discharge of the lamp 2 heat generated is ensured. On the basis of experiments, the dependence of the heat flow per shaft width depending on the width of the gap 60 between the individual cooling fins 6 with different shaft heights as parameters and the heat flow per shaft width as a function of the shaft height with different gap thicknesses as parameters for different wall temperatures of the cooling fins 6 determined and applied as a curve.

from that it turns out that for too small gap thickness hardly a cooling effect is due, because because of the unfavorable ratio from surface to volume the friction is excessively large compared to the buoyancy forces. at increasing gap thickness increases the cooling effect initially steep finally Asymptotically approaching a constant value, as air packets to far away from the heated surface lie, not warmed up anyway can be and therefore are not involved in the convection flow.

In determining an optimal distance of the cooling fins 6 at given dimensions of the headlight housing 1 It should be taken into consideration that, with a smaller gap thickness, more cooling fins are required 6 in the spotlight housing 1 can be accommodated, but their effect disproportionately decreases, while at too great a distance space is given away. The respective optima are where, in the above-mentioned curves, the tangents passing through the origin come into contact with the curves.

Taking into account the of the lamp 2 emitted heat, the ambient temperature and the available space can thus optimal dimensioning of the cooling fins 6 or the cooling disk packs 61 . 62 and thus the convective cooling box 5 be determined. This results, for example, at a wall temperature of 200 degrees C and one between the cooling fins 6 a trained shed height of 0.5 m an optimal gap thickness of 8 mm.

According to the 2 and 3 will be the one from the lamp 2 released heat through the upper cooling fin package 61 guided and in the area of the upper, trapezoidal part 12 of the spotlight housing 1 delivered in the a cover plate 8th with laterally downwards around bent ends 81 . 82 and ribbed outer surface 80 is arranged, the optimum heat distribution in the upper, trapezoidal part 12 of the spotlight housing 1 causes.

Alternatively to a parallel arrangement of the cooling fins 6 The cooling fins can also be tilted against each other so that an optimal cooling air flow also sets when the cooling fins 6 be heated asymmetrically.

To the swirling at the outlet of the heated air at the upper end of the cooling fins 6 under the cover plate 8th To keep as low as possible, the cooling fins 6 convective cooling box 5 be dimensioned differently long, so that, for example, the inner cooling fins 6 are longer than the outer, leaving the upper ends of the cooling fins 6 escaping heated air can dodge sideways more easily.

For the same reason, the cooling fins can 6 also be bent outwards at its upper end and thus support the lateral removal of the heated air.

As in particular the cross-sectional representation according to 3 it can be seen extending the cooling fins 6 over the entire height of the headlamp and thus allow optimum convective air flow and largely foreclosure of the cooling system from the interior of the headlight housing 1 , As a result, the remaining interior of the spotlight housing 1 largely relieved of the heat radiation, so that a greater latitude for the design of the headlight housing 1 is created and the accommodation of heat-sensitive components inside the headlight housing 1 as cable, electronic components and the like is possible.

For optimum heat transfer from the lamp socket 4 to the upper and lower cooling disc pack 61 . 62 points the lamp socket 4 according to 3 comb-like recesses or slots 40 on, in which the cooling fins 6 engage with play, so that no thermal stresses between the cooling fins 6 and the lamp socket 4 may occur. These comb-shaped characteristics serve for better heat transfer into the cooling fins 6 without being between the lamp socket 4 and the cooling fins 6 or the convective cooling box 5 Thermal stresses occur and damage the lamp socket 4 or the cooling fins 6 being able to lead.

To protect the reflector 3 according to the 2 and 4 to 6 have the front in the direction of radiation of the headlight edges 64 the cooling fins 6 one of the contour of the reflector 3 adapted form. This adaptation of the leading edges 64 the cooling fins 6 to the contour of the reflector 3 causes a good heat transfer from the reflector 3 to the convective cooling box 5 , where the cooling fins 6 optionally loose on the outer wall of the reflector 3 abutment or on the reflector 3 can be attached to this way, the heat transfer from the reflector 3 on the cooling fins 6 and thus on the convective cooling box 5 to optimize.

Another benefit of adjusting the leading edges 64 the cooling fins 6 to the contour of the reflector 3 is that a good heat transfer from the reflector 3 on the cooling fins 6 and thus on the convective cooling box 5 is guaranteed even when the headlamp is operated inclined.

In addition to the reflector 3 mounted cooling fins, the comb-like in the cooling fins 6 the convective cooling box intervene, provide a good heat transfer from the reflector 3 to the convective cooling box 5 also safe, if to change the emission characteristics of the headlamp, a relative movement between the reflector 3 and the bulb 2 and with that the bulb 2 partially surrounding convective cooling box 5 is provided.

For better dissipation of the front of the reflector 3 in the area between the reflector 3 and the front cover 14 occurring heat can be provided in the reflector surface recesses in the between the cooling fins 6 open out formed column, so that a heat flow from the front space of the headlamp to the convective cooling box 5 is generated and thus the burden of both the reflector 3 as well as the front cover 14 or the front part 13 the headlight housing is reduced. This additional convective flow is particularly useful when using so-called "facet reflectors" whose light-reflecting surface is formed from a multiplicity of individual facets. "By discharging individual facets or parts of individual facets, openings for heat removal can be produced. without this leading to a significant deterioration of the light emitted by the Scheinwerter amount of light.

In the in the 7 to 10 illustrated embodiments of the reflector 3 are recesses to optimize cooling 36 provided where whole rows or columns of facets 33 of the reflector 3 are released.

In the 7 and 8th a reflector is shown in which an annular recess 36 in the surface of the reflector 3 through a ring 35b ' of facets 33 is covered, the ring 35b ' is formed of a plurality of facet lines, an enlarged diameter and a greater height than the reflector 3 in the area of the recess 36 and thus viewed from the reflector axis from behind the actual reflector 3 is arranged. In this way, a reflector assembly with a recess 36 created in the example, a cooling air flow into the interior of the reflector 3 into and through the reflector 3 can penetrate and at the same time the optical behavior of the reflector 3 is not affected.

The cover to the recess 36 serving ring 35b ' is radially from the actual reflector 3 spaced apart, extends substantially parallel to the original surface of the reflector 3 in the area of the recess 36 and overlaps in the direction of the reflector axis, the respective adjacent rings 35a . 35c Thus, viewed from the reflector axis, in particular from the possible lamp positions on the reflector axis of the recess 36 completely cover up. In this way, the losses caused by the recess 36 in the reflector 3 scattered light emerge, diminished, so that the We degree of cognition and the light distribution produced in the manner described with recesses 36 provided reflector 3 not significantly affected, the cooling effect but against a removal of individual facets 33 but significantly increased.

In the in the 9 and 10 illustrated reflector 3 is a recess 36 created for a cooling flow by a sector-shaped range of facets 33 of the reflector 3 released and by a radially spaced, as seen from the reflector axis from behind the actual reflector 3 arranged sector 34 ' is covered. The sector 34 ' is through multiple columns of facets 33 formed and extends substantially parallel to the original surface of the reflector 3 in the area of its recess 36 , From the 9 it can be seen that the sector 34 ' on the one hand is increased in its height along the reflector axis and in the radial direction perpendicular to the reflector axis, and on the other hand viewed from the reflector axis outwards, ie in the radial direction relative to the actual reflector 3 is arranged offset. The sector 34 ' can additionally along the order fate of the reflector 3 be formed perpendicular to the reflector axis so that it in the circumferential direction of the sector 34 ' overlapping adjacent sectors.

A reflector 3 according to the 7 to 10 thus has a recess 36 on, by means of which an effective cooling of the reflector 3 and the lamp 2 in the interior of the reflector 3 is arranged and enclosed by this is possible, wherein, by the formation and the spatial arrangement of the one portion to cover the recess 36 training sector 34 ' or rings 35b ' the light output and light distribution of the headlamp is not significantly affected, so that the headlight comparable efficiency as an arrangement with a closed reflector 3 having.

It should be noted that the 7 to 10 not drawn to scale and in particular the radial distance between the serving for cover section 34 ' . 35b ' and the reflector 3 can be smaller than shown.

In the embodiments of the reflector 3 according to the 7 to 10 This can be achieved by changing the facets 33 in terms of their curvature and their arrangement in the ring 35b ' or the sector 34 ' causes the reflector provided with the recess 3 generated light distribution is comparable to the light distribution in a closed reflector 3 ,

Moreover, it is conceivable not just a recess by taking out entire rows or columns of facets 33 of the reflector 3 but by omitting, displacing and / or scaling multiple rings 35b ' and / or sectors 34 ' of facets 33 several recesses in the reflector 3 to achieve a further improvement of the cooling.

In addition to the convective cooling device described above, the cooling system according to the invention in the lower, polygonal functional housing 11 arranged ventilation shafts 18 according to 3 on, via the cooling air in the between the convective cooling box 5 and the cylindrical lamp housing 10 trained inside of the headlight housing 1 is directed. This cooling air leads from the side plates 51 . 52 convective cooling box 5 heat released by convection flow to the upper, trapezoidal part 12 of the spotlight housing 1 and thus prevents heat accumulation in this part of the housing interior. The cooling air passes through outside the spotlight housing 1 arranged air inlet openings of the ventilation shafts 18 to the inside of the spotlight housing 1 opening air outlet openings and the convective cooling box 5 in the upper, trapezoidal part 12 of the spotlight housing 1 ,

The perspective view according to 5 can be seen as the lamp 22 from the convective cooling box 5 in between the upper cooling fin package 61 and the lower cooling fin package 62 trained space 63 is included and in this space 63 is slidably mounted in the optical axis of the headlamp, that is in the axial direction. Regardless of the position of the lamp 2 will be at least part of the lamp 2 , in particular the lamp base 22 from the convective cooling box 5 enclosed, allowing optimum heat transfer and thus fast, laminar airflow to drain off the lamp 2 heat is ensured.

As a further feature of the cooling system for headlights according to the invention is according to the 5 and 6 a V-shaped heat sink 7 with the lamp base 22 connected, which are the most sensitive to heating components of the headlight as the inside of the headlight housing 1 led lamp cable 171 . 172 as well as the contact plug 41 . 42 the lamp socket 4 protects against excessive heating by the heat sink 7 shields these components from the heat radiation and the above the lamp base 22 conducted heat to the outside, in particular to the upper and lower cooling fin package 61 . 62 convective cooling box 5 derives.

The connection of the heat sink 7 With the lamp base 22 is preferably carried out by attaching the trained as Aufsteckteil Wärmeableitblechs 7 on the lamp base 22 or the lamp neck, wherein the heat dissipation plate 7 is formed so that it rests as possible form-fitting on the lamp neck to the current from the bulb 2 discharged hot air against the emission direction of the headlamp, that is to the rear, foreclose.

Alternatively to the connection of the heat sink 7 with the lamp base 22 or the lamp neck, the heat dissipation plate 7 be connected with a separate lamp clamping, which is for mechanical relief of the pins of the lamp 2 or the contact plug of the headlamp is provided and the lamp cap 22 includes and secures mechanically.

The embodiment described above was based on an axially adjustable and adjustable in the optical axis of the headlamp lamp 2 illustrated, but is not limited to this form of arrangement of a lamp or a burner. Thus, the cooling system according to the invention can of course also be used in a spherical optical system in which the lamp is perpendicular to a reflector or in the double capped lamps are used, which are installed transversely to the reflector and possibly in a recess of the reflector. Also in these variants, the above-described convective cooling device as well as the heat sink can be used advantageously.

1

headlamp housing

2

Lamp (Lamp or burner)

3

reflector

4

Lamp holder (Lamp holder)

5

convective cooling box

6

cooling fins

7

heat sink

8th

cover

10

lamp housing

11

function housing

12

upper, trapezoidal Part of the headlight housing

13

front of the spotlight housing

14

cover plate or lens

15

headlight bracket

18

ventilation shafts

21

glass vessel

22

Lamp Socket (Lamp cap)

31

First opening of the reflector

32

Second opening of the reflector

33

facet

34 34 '

sector

35a-e, 35b '

ring

36

recess

51 52

side panels

60

column

61

upper Cooling fin pack

62

lower Cooling fin pack

63

gap

64

leading edge the cooling fins

80

ribbed Outer surface of the cover

81, 82

to bottom bent ends of the ribbed outer surface

171 172

supply lines

Claims (35)

Cooling system for a headlamp with a headlight housing, in which a light-emitting means for receiving a light source and a reflector are arranged, which reflects the light emitted from the lamp light beams to a light exit opening of the headlight housing, which is covered with a translucent glass, characterized by a the light source ( 2 ) partially enclosing convective cooling device ( 5 . 51 . 52 ; 6 . 60 - 64 ) for generating a convection flow, that of the light source ( 2 ) dissipates emitted heat. Cooling system according to claim 1, characterized in that the convective cooling device ( 5 . 51 . 52 ; 6 . 60 - 64 ) produces a substantially fast, laminar flow of cooling air. Cooling system according to claim 1 or 2, characterized in that the convective cooling device ( 5 . 51 . 52 ; 6 . 60 - 64 ) a plurality of parallel or inclined mutually arranged cooling fins ( 6 ) having. Cooling system according to claim 3, characterized in that the mutually parallel cooling fins ( 6 ) are aligned in the direction of gravity. Cooling system according to claim 3, characterized in that the cooling fins ( 6 ) are inclined against each other in asymmetric heating in such a way that in all between the cooling fins ( 6 ) formed columns ( 60 ) maintains a substantially laminar flow of cooling air. Cooling system according to at least one of the preceding claims, characterized in that the cooling fins ( 6 ) are formed at least partially different lengths. Cooling system according to claim 6, characterized in that the centrally arranged Kühlla to peel ( 6 ) are longer than the outer cooling fins ( 6 ). Cooling system according to at least one of the preceding claims, characterized in that the preferably upper ends of the cooling fins ( 6 ) to the sides of the plurality of cooling fins ( 6 ) are bent. Cooling system according to at least one of the preceding claims, characterized in that the cooling fins ( 6 ) extend over the entire height of the headlamp. Cooling system according to at least one of the preceding claims, characterized in that the cooling fins ( 6 ) to cooling fin packages ( 61 . 62 ) summarized in the direction of gravity above and below the bulb ( 2 ) are arranged. Cooling system according to claim 10, characterized in that the gap thickness of the between the cooling fins ( 6 ) formed columns ( 60 ) at least as a function of the wall temperature of the cooling fins ( 6 ) and the height of the cooling fin packages ( 61 . 62 ) is determined. Cooling system according to claim 10 or 11, characterized in that the cooling fins ( 61 . 62 ) by two-sided side panels ( 51 . 52 ) to form a convective cooling box ( 5 ) are limited. Cooling system according to claim 12, characterized in that the width of the convective cooling box ( 5 ) substantially to the width of the bulb ( 2 ) is adjusted. Cooling system according to at least one of the preceding claims, characterized in that the upper cooling disk pack ( 61 ) or the convective cooling box ( 5 ) from the upper part ( 12 ) of the headlight housing ( 1 ) led out and by a cover plate ( 8th ) is covered. Cooling system according to claim 14, characterized in that the cover plate ( 8th ) to the spotlight housing ( 1 ) angled ends ( 81 . 82 ) having. Cooling system according to one of claims 12 to 15, characterized in that the convective cooling box ( 5 ) in which between the upper and lower cooling fin package ( 61 . 62 ) formed space ( 63 ) the bulb holder ( 4 ). Cooling system according to claim 16, characterized in that the bulb socket ( 4 ) upper and lower comb-shaped forms or cuts ( 40 ), in which at least a part of the cooling fins ( 6 ) engages with movement scope. Cooling system according to at least one of the preceding claims, characterized in that the front edges in the emission direction of the headlight ( 64 ) of the cooling fins ( 6 ) the shape of the reflector ( 3 ) and the reflector ( 3 ) substantially. Cooling system according to claim 18, characterized in that the leading edges ( 64 ) of the cooling fins ( 6 ) on the reflector ( 3 ) issue. Cooling system according to claim 18 or 19, characterized in that the cooling fins ( 6 ) on the reflector ( 3 ) are attached. Cooling system according to at least one of the preceding claims, characterized in that the rear side of the reflector ( 3 ) is provided with cooling fins, the comb-shaped in between the cooling fins ( 6 ) of the convective cooling box ( 5 ) formed column ( 60 ) intervene. Cooling system according to at least one of the preceding claims, characterized in that the reflector ( 3 ) Has ventilation openings in the between the cooling fins ( 6 ) formed column ( 60 ). Headlamp according to claim 22, characterized in that one or more rows of facets ( 33 ) comprehensive annular region of the reflector ( 3 ) is released and so a recess ( 36 ) in the area of the reflector ( 3 ) is provided, through which a flow of cooling air through the reflector ( 3 ) can flow. Headlight according to claim 22 or 23, characterized in that one or more columns ( 34 ) of facets ( 33 ) extensive area of the reflector ( 3 ) is released and so a recess ( 36 ) in the surface of the reflector ( 3 ) is provided, through which a flow of cooling air through the reflector ( 3 ) can flow. Scheinwerter according to one of claims 22 to 24, characterized in that the recess ( 36 ) by one of reflective facets ( 33 ) formed section ( 34 ' . 35b ' ) radiating radially from the surface of the reflector ( 3 ) is spaced and approximately parallel to the surface of the actual reflector ( 3 ) is covered. Headlamp according to claim 25, characterized in that the cover for the recess ( 36 ) formed from facets ( 33 ) formed in their surface shaping and An are such that the reflector ( 3 ) produces the desired light distribution. Cooling system according to at least one of the preceding claims, characterized in that between the glass vessel ( 21 ) and the contact pins of the lamp ( 2 ) a heat sink ( 7 ) and arranged on the cooling fins ( 61 . 62 ) is aligned. Cooling system according to claim 27, characterized in that the heat dissipation plate ( 7 ) V-, U- or S-shaped. Cooling system according to claim 27 or 28, characterized in that the heat dissipation plate ( 7 ) with the bulb socket ( 22 ) connected is. Cooling system according to claim 29, characterized in that the heat dissipation plate ( 7 ) on the bulb socket ( 22 ) is attached. Cooling system according to claim 27 or 28, characterized in that the heat dissipation plate ( 7 ) with the bulb holder ( 4 ), in particular with the Lampenklemmung for the bulb is connected. Cooling system according to at least one of the preceding claims, characterized in that the substantially bulge-shaped lighting means ( 2 ) in the axial direction of the headlight and in a central opening of the reflector ( 3 ) is used. Cooling system according to claim 32, characterized in that the lighting means ( 2 ) and the reflector ( 3 ) are displaceable in the axial direction against each other. Cooling system according to at least one of the preceding claims 1 to 31, characterized in that the lighting means ( 2 ) is aligned in the direction of gravity (perpendicular) and that the cooling lamellae ( 61 . 62 ) or the convective cooling box ( 5 ) on the reflector ( 3 ) or with the reflector ( 3 ) are connected. Cooling system according to at least one of the preceding claims 1 to 31, characterized in that the lighting means ( 2 ) aligned transversely to the direction of gravity (horizontal) and in a recess of the reflector ( 3 ), and that the cooling fin packets ( 61 . 62 ) or the convective cooling box ( 5 ) on the reflector ( 3 ) or with the reflector ( 3 ) are connected.